Prepare pizza dough and let rise. While dough is rising, combine sage, pine nuts and finely grated parmesan cheese in a food processor and blend until combined. Stream in the olive oil and blend until a pesto forms. Set aside.
Heat a large skillet over medium heat and add 1 tablespoon butter. Toss in butternut squash cubes, along with salt, pepper and nutmeg, tossing to coat. Cover and let cook for 10 minutes, stir, then let cook another 5-10 minutes more, until the cubes are soft but not mushy. Set aside. In the same skillet, add another 1/2 tablespoon of butter with the red onion and a pinch of salt. Cover and let caramelize for 15-20 minutes, stirring occasionally. Once the onions are finished, remove them from the skillet and toss in the prosciutto over low heat, stirring occasionally with a fork.
Preheat oven to 375°F.
Once dough has risen and you are ready to assemble the pizza, spread 2-3 tablespoons of pesto all over the dough. Use a very thin layer unless you LOVE sage. Top with half of the grated parm, then spread butternut squash on evenly. Add the onions on next. Top with prosciutto pieces, then strategically place goat cheese over the pizza. Sprinkle with remaining parmesan. Bake for 25-30 minutes and enjoy!